/* * relocate_kernel.S - put the kernel image in place to boot * 2005.9.17 kogiidena@eggplant.ddo.jp * * LANDISK/sh4 is supported. Maybe, SH archtecture works well. * * 2009-03-18 Magnus Damm - Added Kexec Jump support * * This source code is licensed under the GNU General Public License, * Version 2.  See the file COPYING for more details. */#include <linux/linkage.h>#include <asm/addrspace.h>#include <asm/page.h> 		.globl relocate_new_kernelrelocate_new_kernel:	/* r4 = indirection_page   */	/* r5 = reboot_code_buffer */	/* r6 = start_address      */ 	mov.l	10f, r0		/* PAGE_SIZE */	add	r5, r0		/* setup new stack at end of control page */ 	/* save r15->r8 to new stack */	mov.l	r15, @-r0	mov	r0, r15	mov.l	r14, @-r15	mov.l	r13, @-r15	mov.l	r12, @-r15	mov.l	r11, @-r15	mov.l	r10, @-r15	mov.l	r9, @-r15	mov.l	r8, @-r15 	/* save other random registers */	sts.l	macl, @-r15	sts.l	mach, @-r15	stc.l	gbr, @-r15	stc.l	ssr, @-r15	stc.l	sr, @-r15	sts.l	pr, @-r15	stc.l	spc, @-r15 	/* switch to bank1 and save r7->r0 */	mov.l	12f, r9	stc	sr, r8	or	r9, r8	ldc	r8, sr	mov.l	r7, @-r15	mov.l	r6, @-r15	mov.l	r5, @-r15	mov.l	r4, @-r15	mov.l	r3, @-r15	mov.l	r2, @-r15	mov.l	r1, @-r15	mov.l	r0, @-r15 	/* switch to bank0 and save r7->r0 */	mov.l	12f, r9	not	r9, r9	stc	sr, r8	and	r9, r8	ldc	r8, sr	mov.l	r7, @-r15	mov.l	r6, @-r15	mov.l	r5, @-r15	mov.l	r4, @-r15	mov.l	r3, @-r15	mov.l	r2, @-r15	mov.l	r1, @-r15	mov.l	r0, @-r15 	mov.l	r4, @-r15	/* save indirection page again */ 	bsr	swap_pages	/* swap pages before jumping to new kernel */	 nop 	mova	11f, r0	mov.l	r15, @r0	/* save pointer to stack */ 	jsr	@r6		/* hand over control to new kernel */	 nop 	mov.l	11f, r15	/* get pointer to stack */	mov.l	@r15+, r4	/* restore r4 to get indirection page */ 	bsr	swap_pages	/* swap pages back to previous state */	 nop 	/* make sure bank0 is active and restore r0->r7 */	mov.l	12f, r9	not	r9, r9	stc	sr, r8	and	r9, r8	ldc	r8, sr	mov.l	@r15+, r0	mov.l	@r15+, r1	mov.l	@r15+, r2	mov.l	@r15+, r3	mov.l	@r15+, r4	mov.l	@r15+, r5	mov.l	@r15+, r6	mov.l	@r15+, r7 	/* switch to bank1 and restore r0->r7 */	mov.l	12f, r9	stc	sr, r8	or	r9, r8	ldc	r8, sr	mov.l	@r15+, r0	mov.l	@r15+, r1	mov.l	@r15+, r2	mov.l	@r15+, r3	mov.l	@r15+, r4	mov.l	@r15+, r5	mov.l	@r15+, r6	mov.l	@r15+, r7 	/* switch back to bank0 */	mov.l	12f, r9	not	r9, r9	stc	sr, r8	and	r9, r8	ldc	r8, sr 	/* restore other random registers */	ldc.l	@r15+, spc	lds.l	@r15+, pr	ldc.l	@r15+, sr	ldc.l	@r15+, ssr	ldc.l	@r15+, gbr	lds.l	@r15+, mach	lds.l	@r15+, macl 	/* restore r8->r15 */	mov.l	@r15+, r8	mov.l	@r15+, r9	mov.l	@r15+, r10	mov.l	@r15+, r11	mov.l	@r15+, r12	mov.l	@r15+, r13	mov.l	@r15+, r14	mov.l	@r15+, r15	rts	 nop swap_pages:	bra	1f	 mov	r4,r0	  /* cmd = indirection_page */0:	mov.l	@r4+,r0	  /* cmd = *ind++ */ 1:	/* addr = cmd & 0xfffffff0 */	mov	r0,r2	mov	#-16,r1	and	r1,r2 	/* if(cmd & IND_DESTINATION) dst = addr  */	tst	#1,r0	bt	2f	bra	0b	 mov	r2,r5 2:	/* else if(cmd & IND_INDIRECTION) ind = addr  */	tst	#2,r0	bt	3f	bra	0b	 mov	r2,r4 3:	/* else if(cmd & IND_DONE) return */	tst	#4,r0	bt	4f	rts	 nop 4:	/* else if(cmd & IND_SOURCE) memcpy(dst,addr,PAGE_SIZE) */	tst	#8,r0	bt	0b 	mov.l	10f,r3	  /* PAGE_SIZE */	shlr2	r3	shlr2	r35:	dt	r3 	/* regular kexec just overwrites the destination page	 * with the contents of the source page.	 * for the kexec jump case we need to swap the contents	 * of the pages.	 * to keep it simple swap the contents for both cases.	 */	mov.l	@(0, r2), r8	mov.l	@(0, r5), r1	mov.l	r8, @(0, r5)	mov.l	r1, @(0, r2) 	mov.l	@(4, r2), r8	mov.l	@(4, r5), r1	mov.l	r8, @(4, r5)	mov.l	r1, @(4, r2) 	mov.l	@(8, r2), r8	mov.l	@(8, r5), r1	mov.l	r8, @(8, r5)	mov.l	r1, @(8, r2) 	mov.l	@(12, r2), r8	mov.l	@(12, r5), r1	mov.l	r8, @(12, r5)	mov.l	r1, @(12, r2) 	add	#16,r5	add	#16,r2	bf	5b 	bra	0b	 nop 	.align 210:	.long	PAGE_SIZE11:	.long	012:	.long	0x20000000 ! RB=1 relocate_new_kernel_end: 	.globl relocate_new_kernel_sizerelocate_new_kernel_size:	.long relocate_new_kernel_end - relocate_new_kernel